Blizzard's latest Ask the Devs covers PvP in Patch 5.3. There are some big changes in store, including an ilvl 496 cap in arena and RBGs, as well as resilience removed from all current PvP gear. Players asked questions about the following topics:

PvP Item Level Cap: since all gear will scale down to 496 in arenas and RBGs, players were concerned about PvE trinkets with strong procs, and if the feeling of excitement is now gone when you buy/upgrade gear.

Resilience: Players now get 65% base resilience, and resilience is removed from all current PvP gear. However, PvP resilience remains on heirlooms as well as gems and enchants, but may change in the future. Tank flag carriers now take additional damage in battlegrounds as a way to discourage PvE-geared tank flag carriers.

Rewards and Incentives: Elite gear is now meant to be a vanity reward, similar to the Challenge Mode transmog sets. The team agrees that there's room for more PvP rewards in between, such as a reward for winning 50 Battlegrounds.

Class Changes: Players were most curious about changes to Demonic Gateway (requires a four second cast time, is attackable), and (10 minute cooldown for Shadow Priests).